(1 中国建筑科学研究院有限公司, 北京 100013; 2 中国建筑技术集团有限公司, 北京 100013;3 北京宝维森新材料科技发展有限公司, 北京 101112)

摘要: 缓粘结预应力混凝土梁由无粘结预应力混凝土梁转变为有粘结预应力混凝土梁的判定标准是结构投入正常使用状态的重要依据. 在缓凝粘合剂不同锥入度和不同邵氏硬度条件下,对 15 根缓粘结预应力混凝土梁进行抗弯性能试验,建立缓粘结预应力混凝土梁开裂荷载、裂缝数量和极限承载力与锥入度、邵氏硬度的关系. 同时,与 2 根有粘结预应力混凝土梁和 2 根无粘结预应力混凝土梁的抗弯性能试验作对比. 结果表明:当缓凝粘合剂邵氏硬度达到 50D 时,缓粘结预应力混凝土梁达到有粘结预应力混凝土梁的抗弯性能,即缓粘结预应力混凝土梁转变为有粘结预应力混凝土梁. 据此定义缓凝粘合剂邵氏硬度 50D 为有效硬度. 在以上试验的基础上,制作 3 组缓凝粘合剂抗压试件,测得抗压试件邵氏硬度达到 50D 时,缓凝粘合剂抗压强度为 10MPa,并定义此为有效强度.

关键词: 预应力混凝土梁; 缓凝粘合剂; 抗弯性能; 有效硬度; 有效强度

中图分类号:TU378. 2 文献标志码:A 文章编号:1002-848X(2023)08-0113-06

DOI:10. 19701 / j. jzjg. 20210863

Experimental study on effective strength of retarded adhesive for prestressed concrete beams

JIANG Fangxin1,2, CHEN Shangzhi1,2, LI Peixun1,2,3, LI Xianhua1,2, WANG Bo3

(1 China Academy of Building Research, Beijing 100013, China; 2 China Building Technique Group Co. , Ltd. ,Beijing 100013, China; 3 Broad Vision Technology and Materials Co. , Ltd. , Beijing 101112, China)

Abstract: The criterion for the transition of unbonded prestressed concrete beam to bonded prestressed concrete beam is animportant basis for the normal use of the retard-bonded prestressed concrete beams. Under the conditions of different conepenetration and Shore hardness of retarded adhesive, the flexural performance test of 15 retard-bonded prestressed concretebeams was carried out, and the relationship between the cone penetration, Shore hardness, and the cracking load, thenumber of cracks and the ultimate bearing capacity of the retard-bonded prestressed concrete beams was established. At thesame time, it was compared with the flexural performance test of two bonded prestressed concrete beams and two unbondedprestressed concrete beams. The results show that when the Shore hardness of the retarded adhesive reaches 50D, theflexural performance of the retard-bonded prestressed concrete beam can be achieved, that is, the retard-bonded prestressedconcrete beam can be transformed into bonded prestressed concrete beam. It is defined as: the Shore hardness of retardingadhesive 50D is the effective hardness. Based on the above tests, three groups of compressive specimens of retarderadhesive were made. When the Shore hardness of the compressive specimens reaches 50D, the compressive strength of theretarder adhesive is 10MPa, which was defined as the effective strength.

Keywords:prestressed concrete beam; retarded adhesive; flexural performance; effective hardness; effective strength

∗中国建筑科学研究院有限公司科研基金项目(20181802330730041).

第一作者:蒋方新,硕士,高级工程师,主要从事预应力结构工程研究,Email:316271991@ qq. com.

[引用本文] 蒋方新,陈尚志,李佩勋,等. 预应力混凝土梁缓凝粘合剂有效强度试验研究[J]. 建筑结构,2023,53(8):113-118. JIANG Fangxin,CHEN Shangzhi,LI Peixun, et al. Experimental study on effective strength of retardedadhesive for prestressed concrete beams[J]. Building Structure,2023,53(8):113-118.